Cu（001）表面吸附原子擴(kuò)散行為的分子動(dòng)力學(xué)研究.pdf

1、大連理工大學(xué)碩士學(xué)位論文Cu（001）表面吸附原子擴(kuò)散行為的分子動(dòng)力學(xué)研究姓名：王永亮申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：凝聚態(tài)物理指導(dǎo)教師：張慶瑜20061201Cu(00l滾面吸附原子擴(kuò)散行為的分子動(dòng)力學(xué)研究StudyonDiffusionBehaviorofAdatomonCu(001)SurfacebyMolecularDynamicsAbstractDiffusionbehaviorofadatomandaddimerisODeof也em

2、ainresearchingobjectinthe丘eldofthinfilmphysicsStudyonthediffusionofadatomandad—dimeratatomiclevelistheprimarytaskofsimulatingthemechanismofthinfilmgrowthbycomputeranditwillhavesignificantinstructionalmeaningforotlxunders

3、tandingofthephysicale$8睨lceofthinfilmgrowthWiththeatomicinteractionpotentialwiththeembeddedatommethods，moleculardynamicssimulationwasusedtostudythev斷ationofCu(eel)乳ⅡfacecausedbyaCuadatomandthehopingbarriersofanotherCuada

4、tominthevicinityoftheCuadatomThentheconceptoftemporarysteadystatesofad—dimerisputforwardandthediffusionofhomoaddimerandhcteroaddimerwithtemporarysteadystatesisstudiedincludingtheirlifespananddiffusionooe伍cientsThemajorpo

5、intsofthisworkw61“esummarizedasfoUows：1Distortionofh城eecausedbyasingleadatomTheresultsshowthattheCuadatommayenablethepositionsofCuatomsinthesubstraterisinginarangeof2latticeconstantsand也einfluenceisasdeepas10layers2neinf

6、luenceofasingleadatomonselfdiffusionofanotheradatomDuetotheinteractionofthestressfieldbetweentwoadatoms，thehopingdiffusionbarriersoftheadatomsaredecreasedandtheadato皿KlemoreactiveindiffusionthanasingleadatomBycomparingth

7、edifferenceofhapingharrierstoingandfioingaloagasamediffusionpaththemigratingbehavioroftheadatomscanbedividedintotwokindsofdiffusiondependingonthedistancebetweenthetwoadatomsIf也eyareinadistancelongerthantheeffectivedistan

8、ceoftheatomicinteractionpotentials，thediffusionofadatomsisaffectedonlybytheinteractionofthestress丘eldbetweentwoadatomsIfthey勰inadistanceshorterthantheeffectivedistanceoftheatomicinteractionpotentialsthetwoadatomsshouldbe

9、considered船anad—d岫indifferenttemporarysteadystates3DiffusionofaddimerwithtemporarysteadystatesWhenthetemperatureislowerthan400Kthead—dinlcrwillvxistforinfintelongtimeforthelifespanislongenoughinthemicrotimescale111ecoeff

10、icientoftheaddimerisconsiderablysmallwhichindicatesweakdiffusivitySothesecondandthirdtemporarysteadystateshasnothingtodowiththediffusionoftheadatomHowever，whenthetemperatureishi曲crthan400Ksometimestheaddimcl“swilldieandw